The invention relates to an apparatus for treating blocks like masonry blocks out of natural or artificial material like concrete.
Walls, in particular for landscape architecture, are preferably produced from natural or manmade blocks which are provided, on the visible side, with a surface structure of irregular relief and/or broken edges, as produced, for example, by the manual working of natural blocks. Concrete blocks can only be produced with essentially planar surfaces. It is also the case, however, that split natural blocks generally have sharp edges.
U.S. Pat. No. 6,109,906 discloses an apparatus for the surface treatment of masonry blocks, the blocks, once formed and hardened, being conveyed along a treatment station to the right and left by means of two conveying arrangements such that they project somewhat in the direction of the treatment station in relation to the respective conveying arrangement. For this purpose, the blocks are transported in a manner in which they are clamped in between the bottom strand and the top strand of two conveyors of the respective conveying arrangement. Located in the treatment station are one or more vertically arranged drums which are equipped, on the circumference, with chains which, at their free ends, bear striking heads which, upon rotation of the drums, alternately come into contact with the surfaces of the blocks guided along to the right and left thereof. As a result, although the visible surface of the blocks is subject to impact treatment, in which case the edges are also broken, it is only the striking heads which take effect here in each case, it being the case, in addition, that said striking heads bounce back onto the block following the impact and have to be moved back into the striking position again by correspondingly high centrifugal force as a result of rapid rotation of the tool holder. This means that the operation of treating the blocks is not very effective, quite apart from the fact that a relatively large quantity of waste is also produced as a result of the impact treatment.
An object of the invention is thus to provide an apparatus for the treatment of blocks which provides a more effective and careful treatment.
A further object of the invention is to provide an apparatus for the treatment of blocks which may be used for a treating a surface of the blocks which treating is variable in a desired manner.
A further object of the invention is to provide an apparatus for the treatment of blocks with an enhanced speed.
According to the invention an apparatus for treating blocks is provided, comprising:
a treatment station with at least one rotatable tool holder;
a conveying device for transporting the blocks one after the other along the treatment station;
the at least one rotatable tool holder having a longitudinal axis and flexible, elongate treatment tools having two ends mounted thereon, wherein the flexible treatment tools come into contact with predetermined regions of the blocks as the tool holder rotates; and
the tools are fastened in loop form, by way of the two ends, on the tool holder such that they are spaced apart from one another in the direction of the longitudinal axis of the latter, with the result that they sag when the tool holder is at a standstill.
Since use is made of loop-form treatment tools which are fastened on the tool holder, by way of the two ends, such that they are spaced apart from one another in the direction of the longitudinal axis of the latter, with the result that they sag when the tool holder is at a standstill and spread out in arcuate form in the outward direction on account of the centrifugal force as the tool holder rotates, the flexible treatment tools conform to the blocks as they strike them and treat the blocks over a corresponding length and, moreover, essentially with abrading and/or grating action, with the result that the treatment is careful, on the one hand, and very effective, on the other hand.
The action can be enhanced or reduced by adjusting the distance between the tool holder and block surface as well as by the rotational speed, depending on the degree of roughness desired for the configuration. The action may be also varied by variation of the transportation speed of the blocks along the treatment tools.
Further objects, advantages and embodiments of the invention are evident from the following description.